Coal dry-distillation device and modified coal production equipment using same

ABSTRACT

A rotary kiln-type coal dry-distillation device that: rotatably supports an inner tube inside an outer tube; supplies heating gas to the interior of the outer tube; moves dried coal from one end side of the inner tube to the other end side, and agitates and dry-distills the dried coal under heat by supplying the dried coal from the one end side of the inner tube to the interior, and rotating the inner tube; sends out dry-distilled coal and dry-distilled gas from the other end side of the inner tube; and has provided therein a pulverized coal supply device that supplies pulverized coal having a particle diameter of no more than 100 μm to the interior of the inner tube, such that the volume of the pulverized coal is 1-10 wt % relative to the amount of dry-distilled coal sent from the other end side of the inner tube.

TECHNICAL FIELD

The present invention relates to a coal pyrolysis device and a modified coal production equipment that uses the coal pyrolysis device.

BACKGROUND ART

Low grade coal (low rank coal) with a high moisture content such as lignite and subbituminous coal has a low calorific content per unit weight and therefore such coal is dried and pyrolyzed by heating and then modified so that the surface activity is reduced in a low oxygen atmosphere, whereby the low grade coal is turned into modified coal having a high calorific content per unit weight while preventing spontaneous combustion.

A rotary kiln-type device is known as a coal pyrolysis device for pyrolyzing dried coal obtained by drying low grade coal. The rotary kiln-type device rotatably supports an inner tube (main body trunk) inside an outer tube (jacket) that is fixed and supported, and pyrolyzes under heat while moving and agitating the dried coal from the one end side of the inner tube to the other end side thereof, by rotating the inner tube when heating gas is supplied to the interior of the outer tube (between the outer tube and the inner tube) and when the dried coal is supplied from the one end side of the inner tube to the interior thereof; so as to send out pyrolyzed coal and pyrolyzed gas from the other end side of the inner tube.

CITATION LIST Patent Literature

Patent Document 1: Japanese Unexamined Patent Application Publication No. 2003-176985A

Patent Document 2: Japanese Unexamined Patent Application Publication No. 2004-003738A

Patent Document 3: Japanese Unexamined Patent Application Publication No. H10-230137A

Patent Document 4: Japanese Unexamined Patent Application Publication (translation of PCT application) No. 2009-539605A

SUMMARY OF THE INVENTION Technical Problem

However, when the dried coal is pyrolyzed, in addition to carbon monoxide, water vapor, tar, and the like, a pyrolyzed gas (pyrolysis gas) is also generated containing minute amounts of mercury-based substances such as HgS and HgCl₂ included in the dried coal.

Moreover, while the inside of the inner tube (main body trunk) in the aforementioned rotary kiln-type coal pyrolysis device is covered by the outer tube (jacket) and the portion (middle in the axial direction) heated by the heating gas is able to maintain a high temperature, a portion (other end side in the axial direction) that protrudes from the outer tube so as not to be covered by the outer tube and that is not heated by the heating gas has a lower temperature.

As a result, when the pyrolyzed coal and the pyrolyzed gas inside the inner tube of the coal pyrolysis device are moved to the other end side of the inner tube, the temperature is reduced and the mercury-based substances in the pyrolyzed gas adhere to the pyrolyzed coal and thus the pyrolyzed coal sent from the other end side of the inner tube has a higher concentration of mercury.

Accordingly, an object of the present invention is to provide a coal pyrolysis device that is able to suppress an increase in mercury concentration in the generated pyrolyzed coal, and to provide a modified coal production equipment that uses the coal pyrolysis device.

Solution to Problem

In order to resolve the aforementioned problems, a coal pyrolysis device according to a first invention is a rotary kiln-type coal pyrolysis device that rotatably supports an inner tube inside an outer tube and that pyrolyzes under heat while moving and agitating coal from one end side of the inner tube to another end side thereof, by rotating the inner tube when heating gas is supplied to an interior of the outer tube and when the coal is supplied from the one end side of the inner tube to an interior thereof, so as to send out pyrolyzed coal and pyrolyzed gas from the other end side of the inner tube; the coal pyrolysis device including: a pulverized coal supply means that supplies pulverized coal having a particle diameter of less than or equal to 100 μm to the interior of the inner tube, such that a volume of the pulverized coal is 1-10 wt % relative to an amount of the pyrolyzed coal sent from the other end side of the inner tube.

The coal pyrolysis device according to a second invention related to the first invention, wherein the pulverized coal supply means supplies the pulverized coal nearer the other end where a temperature reduction occurs than the middle in the axial direction inside the inner tube.

The coal pyrolysis device according to a third invention related to the first or second inventions, wherein an exhaust nozzle is disposed so that a distal end thereof is positioned between the uppermost position of an opening on the other end side of the inner tube and a surface position of a layer of the pyrolyzed coal present in the lowest position of the opening on the other end side of the inner tube, whereby the pyrolyzed gas is sent out from the other end side of the inner tube.

In order to solve the above problem, a modified coal production equipment according to a fourth invention includes a coal drying means for drying coal and the coal pyrolysis device described in any of the first to third inventions for pyrolyzing dried coal dried with the coal drying means.

The modified coal production equipment according to a fifth invention related to the fourth invention, includes a pyrolyzed coal cooling means for cooling the pyrolyzed coal pyrolyzed by the coal pyrolysis device.

The modified coal production equipment according to a sixth invention related to the fifth invention includes a deactivation treatment means for deactivating the pyrolyzed coal cooled by the pyrolyzed coal cooling means using an oxygen-containing gas.

The modified coal production equipment according to a seventh invention related to the fourth invention, wherein the pulverized coal supply means supplies pulverized coal generated and recovered accompanying the drying of the coal by the coal drying means.

The modified coal production equipment according to an eighth invention related to the fifth invention, wherein the pulverized coal supply means supplies pulverized coal that is a portion of the pyrolyzed coal cooled by the pyrolyzed coal cooling means that is extracted and pulverized.

The modified coal production equipment according to a ninth invention related to the sixth invention, wherein the pulverized coal supply means supplies pulverized coal recovered from the oxygen-containing gas used in the deactivation treatment of the pyrolyzed coal by the deactivation treatment means.

Advantageous Effects of Invention

According to the coal pyrolysis device and the modified coal production equipment that uses the coal pyrolysis device of the present invention, because the pulverized coal supply means supplies pulverized coal with a particle diameter of less than or equal to 100 μm to the interior of the inner tube so that the volume of the pulverized coal is 1-10 wt % relative to the amount of the pyrolyzed coal sent from the other end side of the inner tube, when the pulverized coal and the pyrolyzed coal are positioned toward the other end side of the interior of the inner tube, that is, a portion in which the pulverized coal and the pyrolyzed coal are not heated by the heating gas, and when the temperature of the pulverized coal and the pyrolyzed coal is reduced, a larger portion of the mercury-based substances in the pyrolyzed gas adheres to the pulverized coal than to the pyrolyzed coal because the particle diameter of the pulverized coal is much smaller than the particle diameter of the pyrolyzed coal and the surface area of the pulverized coal per unit weight is much larger than that of the pyrolyzed coal, whereby an increase in the generated mercury concentration in the pyrolyzed coal is suppressed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic configuration diagram of a first embodiment of a modified coal production equipment according to the present invention.

FIG. 2 is a schematic configuration diagram of a main portion of the coal pyrolysis device depicted in FIG. 1.

FIG. 3 is a schematic configuration diagram of a second embodiment of the modified coal production equipment according to the present invention.

FIG. 4 is a schematic configuration diagram of a main portion of the coal pyrolysis device depicted in FIG. 3.

FIG. 5 is a schematic configuration diagram of a third embodiment of the modified coal production equipment according to the present invention.

FIG. 6 is a schematic configuration diagram of a fourth embodiment of the modified coal production equipment according to the present invention.

FIG. 7 is a schematic configuration diagram of a main portion of the coal pyrolysis device of a fifth embodiment of the modified coal production equipment according to the present invention.

FIG. 8 is a schematic configuration diagram of a waste gas treatment device of a sixth embodiment of the modified coal production equipment according to the present invention.

DESCRIPTION OF EMBODIMENTS

While embodiments of the coal pyrolysis device and the modified coal production equipment using the same according to the present invention will be described on the basis of the drawings, the present invention is not limited to the following embodiments described on the basis of the drawings.

First Embodiment

A first embodiment of a coal pyrolysis device and a modified coal production equipment using the same is described below on the basis of FIGS. 1 and 2.

As illustrated in FIG. 1, a coal drying device 110, which is a coal drying means for drying low-grade coal (low rank coal) 1 with a high water content such as lignite or subbituminous coal, includes: a hopper 111 for receiving the low grade coal 1; an inner tube (main body trunk) 112 that is rotatably supported and into which the low-grade coal 1 inside the hopper 111 is supplied from one end side (proximal end side); an outer tube (jacket) 113 fixed and supported so as to cover an outer circumferential surface of the inner tube 112 while allowing the inner tube 112 to rotate, steam 11 that is a heating medium being supplied to the inside (between the inner tube 111 and the outer tube 113) of the outer tube 113; and a chute 114 that is coupled to the other end side (distal end side) of the inner tube 112 so as to allow rotation of the inner tube 112 and that sends out dried coal 2 so as to make the dried coal 2 fall downward from the other end side (distal end side) of the inner tube 112.

The distal end side of an inert gas feeding line 115 for feeding an inert gas 12 such as nitrogen gas is coupled to the one end side (proximal end side) of the inner tube 112 of the coal drying device 110. The one end side of an exhaust line 116 for exhausting the inert gas 12 containing carbon monoxide, water vapor and the like is coupled to an upper part of the chute 114. The other end side of the exhaust line 116 is coupled to a cyclone separator 117 for separating and recovering pulverized coal 2 a from the inert gas 12, the pulverized coal 2 a being generated accompanying the drying of the low grade coal 1.

The one end side (proximal end side) of a recirculating line 118 having a condenser 118 a for separating and removing water vapor by condensing into water 13 in the inert gas 12 in which the pulverized coal 2 a is separated, is coupled to the cyclone separator 117. The other end side (distal end side) of the recirculating line 118 is coupled to the inert gas feeding line 115 in the middle thereof.

The lower part of the chute 114 of the coal drying device 110 communicates with the upstream side in the conveying direction of a dried coal conveying line 119 such as a conveyor belt for conveying the dried coal 2 sent from the chute 114. The downstream side in the conveying direction of the dried coal conveying line 119 communicates with a coal pyrolysis device 120 for pyrolyzing the dried coal 2.

As illustrated in FIGS. 1 and 2, the coal pyrolysis device 120 includes: a hopper 121 for receiving the dried coal 2 from the dried coal conveying line 119; an inner tube (main body trunk) 122 that is rotatably supported and into which the dried coal 2 inside the hopper 121 is supplied from one end side (proximal end side); an outer tube (jacket) 123 that is fixed and supported so as to cover an outer circumferential surface of the inner tube 122 while allowing the inner tube 122 to rotate and into which a heating gas 17 is supplied as a heating medium (between the inner tube 121 and the outer tube 123); and a chute 124 that is coupled to the other end side (distal end side) of the inner tube 122 so as to allow the inner tube 122 to rotate and that sends out the pyrolyzed coal 3 so as to make the pyrolyzed coal 3 fall downward from the other end side (distal end side) of the inner tube 122.

As illustrated in FIG. 1, the one end side (proximal end side) of an exhaust line 126 for exhausting pyrolyzed gas (pyrolysis gas) 14 such as carbon monoxide, water vapor, and tar is coupled to an upper part of the chute 124 of the coal pyrolysis device 120. The other end side (distal end side) of the exhaust line 126 is coupled to a combustion furnace 127 into which air 15 and a combustion improver 16 are supplied.

An extracting line 128 that extracts from the recirculating line 118 a portion of the inert gas 12 from which water 13 is removed by the recirculating line 118 in the coal drying device 110 and that supplies the portion of the inert gas 12 into the combustion furnace 127, is coupled to the combustion furnace 127. The one end side (proximal end side) of a heating gas feeding line 125 for feeding heating gas 17 generated inside the combustion furnace 127, is coupled to the combustion furnace 127. The other end side (distal end side) of the heating gas feeding line 125 communicates with the inside of the outer tube 123.

The lower part of the chute 124 of the coal pyrolysis device 120 communicates with a cooling device 130 that is a pyrolyzed coal cooling means for cooling the pyrolyzed coal 3 sent from the chute 124. The cooling device 130 is provided with: a hopper 131 for receiving the pyrolyzed coal 3 from the chute 124 of the coal pyrolysis device 120; an inner tube (main body trunk) 132 that is rotatably supported and into which the pyrolyzed coal 3 is supplied from the hopper 131 from the one end side (proximal end side) and inside which cooling water 18 is sprayed; an outer tube (jacket) 133 that is fixed and supported so as to cover the outer circumferential surface of the inner tube 132 while allowing the inner tube 132 to rotate; and a chute 134 that is coupled to the other end side (distal end side) of the inner tube 132 so as to allow the inner tube 132 to rotate and that sends out the cooled pyrolyzed coal 3 so as to make the cooled pyrolyzed coal 3 fall downward from the other end side (distal end side) of the inner tube 132.

The lower part of the chute 134 in the cooling device 130 communicates with the upstream side in the conveying direction of a pyrolyzed coal conveying line 139 such as a conveyor belt for conveying the pyrolyzed coal 3 sent from the chute 134. The downstream side in the conveying direction of the pyrolyzed coal conveying line 139 communicates with an upper part of a tower body 141 of a deactivation treatment device 140 that is a deactivation treatment means for deactivating the pyrolyzed coal 3. An air feeding line 142 having an air blower 142 a for feeding air 15 which is an oxygen-containing gas into the tower body 141, is coupled to the tower body 141.

A lower part of the tower body 141 of the deactivation treatment device 140 communicates with a kneading device 151 which is a kneading means for kneading deactivated modified coal 4 with a binder 5 such as starch and water 6. The kneading device 151 communicates with a compressing device 152 which is a compressing means for molding by compressing the modified coal 4 kneaded with the binder 5 and the water 6 into molded coal 7.

The one end side (proximal end side) of a waste air line 143 for sending out waste air 19, which is oxygen-containing air used for deactivating the pyrolyzed coal 3, from the inside of the tower body 141 is coupled to the tower body 141 of the deactivation treatment device 140. The other end side (distal end side) of the waste air line 143 is coupled to a cyclone separator 144 for separating and recovering pulverized coal 4 a in the waste air 19.

A lower part of the cyclone separator 144 of the deactivation treatment device 140 communicates with a pulverized coal conveying device 171 for conveying from the cyclone separator 144 the pulverized coal 4 a separated from the waste air 19. The first side (right side in FIG. 1) of the pulverized coal conveying device 171 communicates with a recovery container 172 for recovering the pulverized coal 4 a.

The second side (left side in FIG. 1) of the pulverized coal conveying device 171 communicates with a hopper 173 for receiving the pulverized coal 4 a. A lower part of the hopper 173 is coupled to the proximal end side of a feeder 174 for sending in fixed amounts the pulverized coal 4 a inside the hopper 173. The distal end side of the feeder 174 communicates with the hopper 121 of the coal pyrolysis device 120 via a conveyor 175.

The one end side (proximal end side) of a waste gas line 161 having a sending blower 161 a for exhausting waste gas 17 a of the heating gas 17 from the inside of the outer tube 113, is coupled to the outer tube 113 of the coal pyrolysis device 120. A condenser 161 b for cooling the waste gas 17 a is provided in the waste gas line 161.

The other end side (distal end side) of the waste gas line 161 communicates with a gas receiving part of a NOx removal device 162 which is a NOx removal means that atomizes an ammonium chloride aqueous solution 21 onto the waste gas 17 a. A gas sending part of the NOx removal device 162 communicates with a gas receiving part of an electric dust collection device 163 which is a dust removal means for separating and removing dust and the like from the waste gas 17 a. A gas sending part of the electric dust collection device 163 communicates with a gas receiving part of desulfurization device 164 which is a desulfurization means for blowing a calcium carbonate slurry 22 into the waste gas 17 a. A gas sending part of the desulfurization device 164 communicates with outside the system.

In this embodiment, the coal drying device 110 is configured by the hopper 111, the inner tube 112, the outer tube 113, the chute 114, the inert gas feeding line 115, the exhaust line 116, the cyclone separator 117, the recirculating line 118, the dried coal conveying line 119, and the like; the coal pyrolysis device 120 is configured by the hopper 121, the inner tube 122, the outer tube 123, the chute 124, the heating gas feeding line 125, the exhaust line 126, the combustion furnace 127, the extracting line 128, and the like; the cooling device 130 is configured by the hopper 131, the inner tube 132, the outer tube 133, the chute 134, the dried coal conveying line 139, and the like; the deactivation treatment device 140 is configured by the tower body 141, the air feeding line 142, the waste air line 143, the cyclone separator 144, and the like; a molded coal manufacturing device 150 which is a molded coal manufacturing means is configured by the kneading device 151, the compressing device 152, and the like; a waste gas treatment device 160 which is a waste gas treatment means is configured by the waste gas line 161, the NOx removal device 162, the electric dust collection device 163, the desulfurization device 164, and the like; the pulverized coal supply device 170 which is a pulverized coal pulverized coal supply means is configured by the pulverized coal conveying device 171, the recovery container 172, the hopper 173, the feeder 174, the conveyor 175, and the like; and the modified coal production equipment 100 is configured by the coal drying device 110, the coal pyrolysis device 120, the cooling device 130, the deactivation treatment device 140, the molded coal manufacturing device 150, the waste gas treatment device 160, the pulverized coal supply device 170, and the like.

Principal operations of the above-mentioned modified coal production equipment 100 will be described first.

When the steam 11 is supplied into the outer tube (jacket) 123 of the coal drying device 110, the low grade coal 1 (average particle diameter: approximately 10 mm) is put into the hopper 111 so that the low grade coal 1 is supplied into the inner tube (main body trunk) 112, and when the inert gas 12 is fed into the inner tube 112, the low grade coal 1 is moved from the one end side to the other end side of the inner tube 112 while being agitated due to the rotation of the inner tube 112 whereby the low grade coal 1 is evenly heat-dried (approximately 150 to 200° C.) to form dried coal 2 (average particle diameter: approximately 5 mm), and the dried coal 2 is sent out via the chute 114 to the dried coal conveying line 119 and supplied to the hopper 121 of the coal pyrolysis device 120.

The inert gas 12 (approximately 150 to 200° C.) fed into the inner tube 112 of the coal drying device 110 is fed with water vapor and pulverized coal 2 a (particle diameter: 100 μm or less) generated accompanying the drying of the low grade coal 1 from the upper part of the chute 114 via the exhaust line 116 to the cyclone separator 117, and the pulverized coal 2 a is separated and then fed to the recirculating line 118. After the inert gas 12 is cooled by the condenser 118 a so that water 13 is separated and removed, a large portion (approximately 85%) of the inert gas 112 is returned to the inert gas feeding line 115 and fed again into the inner tube 112 to be reused along with new inert gas 12, and a portion (approximately 15%) of the inert gas 12 is fed to the combustion furnace 127 of the coal pyrolysis device 120 via the extracting line 128.

The dried coal 2 (approximately 150 to 200° C.) supplied to the hopper 121 of the coal pyrolysis device 120 is fed into the inner tube (main body trunk) 122 and moved from the one end side of the inner tube 122 to the other end side while being agitated due to the rotation of the inner tube 122, whereby the dried coal 2 is evenly pyrolyzed under heat (350 to 450° C.) with the heating gas 17 (approximately 1000 to 1100° C.) fed into the outer tube (jacket) 123 from the combustion furnace 127 via the heating gas feeding line 125 so as to form pyrolyzed coal 3 (average particle diameter: approximately 5 mm), which is supplied via the chute 124 into the hopper 131 of the cooling device 130.

The pyrolyzed gas 14 (approximately 350 to 450° C.) generated accompanying the pyrolysis inside the inner tube 122 of the coal pyrolysis device 120 is fed from the upper part of the chute 124 to the combustion furnace 127 via the exhaust line 126 and is burned along with the inert gas 12 (including carbon monoxide and the like) and air 15 (the combustion improver 16 if required) to be used in the generation of the heating gas 17.

The pyrolyzed coal 3 (350 to 450° C.) supplied to the hopper 131 of the cooling device 130 is fed into the inner tube (main body trunk) 132 and is moved from the one end side to the other end side of the inner tube 132 while being agitated due to the rotation of the inner tube 132, whereby the pyrolyzed coal 3 is evenly cooled (approximately 50 to 60° C.) due to the cooling water 18 being sprayed inside the inner tube 132, and then sent out via the chute 134 to the pyrolyzed coal conveying line 139 to be supplied from above into the tower body 141 of the deactivation treatment device 140.

The cooling water 18 sprayed inside the inner tube 132 of the cooling device 130 is evaporated along with the cooling of the pyrolyzed coal 3 and sent out outside the system as water vapor 20 from the top of the chute 134.

The pyrolyzed coal 3 (approximately 50 to 60° C.) supplied from above into the tower body 141 of the deactivation treatment device 140 is deactivated due to the active spots (radicals) generated during the pyrolysis reacting with oxygen in the air 15 fed by the air blower 142 a in the air feeding line 142 so as to form modified coal 4 (average particle diameter: approximately 5 mm) which is fed from the bottom of the tower body 141 to the kneading device 151.

Waste air 19 (approximately 50 to 70° C.) used in the deactivation treatment of the pyrolyzed coal 3 inside the tower body 141 of the deactivation treatment device 140 is fed along with pulverized coal 4 a (particle diameter: 100 μm or less) generated in the deactivation treatment to the cyclone separator 144 via the waste air line 143, and after being separated from the pulverized coal 4 a, the waste air 19 is exhausted outside the system.

The modified coal 4 (approximately 30° C.) fed to the kneading device 151 is kneaded along with the binder 5 and the water 6 and then fed to the molding device 152 to be compressed and molded to form molded coal 7.

When the dried coal 2 is pyrolyzed during the manufacturing of the molded coal 7 from the low grade coal 1 in this way, gases with minute amounts of mercury-based substances such as HgS and HgCl₂ are included in the pyrolyzed gas 14.

In this case, a temperature reduction occurs in a portion (other end side in the axial direction) of the inner tube 122 that protrudes from the outer tube 123 so as not to be covered by the outer tube 123 and that is not heated by the heating gas 17 in the above-mentioned rotary kiln-type coal pyrolysis device 120. Thus, conventionally, the mercury-based substances re-adhere to the pyrolyzed coal 3 in the portion (other end side in the axial direction) of the inner tube 122 protruding from the outer tube 123 so as not to be covered by the outer tube 123 and thus not heated by the heating gas 17, and the mercury concentration in the pyrolyzed coal 3 sent from the other end side of the inner tube 122 is increased.

In order to suppress the increase in the mercury concentration in the pyrolyzed coal 3, the modified coal production equipment 100 according to this embodiment that addresses this problem further operates as follows.

The pulverized coal 4 a (particle diameter: 100 μm or less) separated and recovered in the cyclone separator 144 of the deactivation treatment device 140 is fed from the lower part of the cyclone separator 144 into the hopper 173 via the pulverized coal conveying device 171, and is fed by the feeder 174 along with dried coal 2 into the hopper 121 of the coal pyrolysis device 120 via the conveyor 175 so that the volume of the pulverized coal 4 a is 1-10 wt % (preferably 3-5 wt %) relative to the amount of the pyrolyzed coal 3 sent from the other end side of the inner tube 122 of the coal pyrolysis device 120, that is the pyrolyzed coal 3 sent falling downward from the chute 124.

If the amount of the pulverized coal 4 a supplied from the cyclone separator 144 into the hopper 173 is too much at this time, the pulverized coal conveying device 171 is made to operate temporarily in the reverse direction so that the excess pulverized coal 4 a is recovered in the recovery container 172.

As illustrated in FIG. 2, while the pulverized coal 4 a supplied to the hopper 121 of the coal pyrolysis device 120 in this way is fed into the inner tube 122 along with the dried coal 2 and moved from the one end side to the other end side of the inner tube 122 while floating inside the inner tube 122 accompanying the rotation of the inner tube 122, the dried coal 2 is evenly pyrolyzed under heat (350 to 450° C.) with the heating gas 17 (approximately 1000 to 1100° C.) as described above to form pyrolyzed coal 3 and, at the same time, the pyrolyzed gas 14 containing gas with minute amounts of a mercury-based substance 23 such as HgS or HgCl₂ is also generated.

When the pulverized coal 4 a and the pyrolyzed coal 3 move toward the other end side of the inner tube 122, that is, the pulverized coal 4 a and the pyrolyzed coal 3 are positioned at the portion not heated by the heating gas 17 and the temperature of the pulverized coal 4 a and the pyrolyzed coal 3 decreases, a larger portion of the mercury-based substance 23 in the pyrolyzed gas 14 adheres to the pulverized coal 4 a than to the pyrolyzed coal 3 because the particle diameter (100 μm or less) of the pulverized coal 4 a is much smaller than the particle diameter (approximately 5 mm) of the pyrolyzed coal 3 and the surface area of the pulverized coal 4 a per unit weight is much larger than that of the pyrolyzed coal 3.

As a result, an increase in the mercury concentration of the pyrolyzed coal 3 sent from the chute 124 of the coal pyrolysis device 120 is suppressed.

Meanwhile, the pulverized coal 4 a to which the mercury-based substance 23 is adhered is fed along with the pyrolyzed gas 14 to the combustion furnace 127, via the exhaust line 126, from the top of the chute 124 of the coal pyrolysis device 120 as illustrated in FIG. 1, whereby the pyrolyzed gas 14 and the pulverized coal 4 a are burned along with the inert gas 12 (including carbon monoxide and the like) and air 15 (the combustion improver 16 if required) as described above to be used in the generation of the heating gas 17.

At this time, the mercury-based substance 23 such as HgS and HgCl₂ adhered to the pulverized coal 4 a becomes present as gaseous Hg in the heating gas 17 (approximately 1000 to 1100° C.) due to the burning.

The waste gas 17 a of the heating gas 17 used in the pyrolysis heating of the dried coal 2 inside the inner tube 122 by being fed into the outer tube 123 of the coal drying device 120 from the combustion furnace 127 via the heating gas feeding line 125 is exhausted from the outer tube 123 to the waste gas line 161, and after being cooled (approximately 350° C.) by the condenser 118 a, the waste gas 17 a is fed via the sending blower 161 a to the NOx removal device 162.

Nitrogen oxides such as nitric monoxide in the waste gas 17 a fed to the NOx removal device 162 are replaced by nitrogen gas and the mercury is replaced by mercury chloride due to the ammonium chloride aqueous solution 21 being atomized (see formulas (1) and (2) below).

4NO+4NH₃+O₂→4N₂+6H₂O  (1)

Hg+½O₂+2HCl→HgCl+2H₂O  (2)

Next, dust and the like in the waste gas 17 a is separated and removed in the electric dust collection device 163 and then the waste gas 17 a is fed to the desulfurization device 164.

The waste gas 17 a fed to the desulfurization device 164 is subjected to post-treatment so that the mercury chloride is dissolved in water and recovered by the calcium carbonate slurry 22 being blown therein, and after sulfur oxides such as sulfur dioxide are replaced by calcium sulfate and the like (see formulas (3), (4), (5) below) and recovered, the waste gas 17 a is exhausted outside the system.

HgCl+H₂O→HgClaq  (3)

SO₂+CaCO₃+½H₂O→CaSO₃.½H₂O+CO₂  (4)

CaSO₃.½H₂O+½O₂+3/2H₂O→CaSO₄. 2H₂O  (5)

In other words, in this embodiment, by supplying the pulverized coal 4 a (particle diameter: 100 μm or less) to the inner tube 122 so that the volume thereof is 1-10 wt % (preferably 3-5 wt %) relative to the amount of the pyrolyzed coal 3 generated in the coal pyrolysis device 120, that is, the amount of the pyrolyzed coal 3 sent from the other end side of the inner tube 122, more of the mercury-based substance 23 in the pyrolyzed gas 14 is made to adhere to the pulverized coal 4 a than to the pyrolyzed coal 3, and the pulverized coal 4 a is separated from the pyrolyzed coal 3 to be exhausted along with the pyrolyzed gas 14.

Therefore, according to this embodiment, an increase in the generated mercury concentration in the pyrolyzed coal 3 to be generated can be suppressed.

Moreover, since unneeded pulverized coal 4 a separated and recovered from the waste air 19 sent from the tower body 141 of the deactivation treatment device 140 is used, the suppression of the increase in the mercury concentration in the pyrolyzed coal 3 can be realized in an extremely low-cost and simple manner.

The particle diameter of the pulverized coal supplied to the inner tube 122 of the coal pyrolysis device 120 needs to be set to 100 μm or less (the size that passes through a 100 μm square mesh). The reason for this is that when the particle diameter exceeds 100 μm, separating the pulverized coal from the pyrolyzed coal 3 and exhausting the pulverized coal with the pyrolyzed gas 14 becomes difficult. Meanwhile, while the lower limit of the particle diameter of the pulverized coal is not limited in particular, practical difficulties may arise if the particle diameter is less than 10 μm and therefore is not desired.

Moreover, the amount of the pulverized coal supplied to the inner tube 122 of the coal pyrolysis device 120 needs to be 1-10 wt % (preferably 3-5 wt %) relative to the amount of the pyrolyzed coal 3 sent from the other end side of the inner tube 122 in the coal pyrolysis device 120. The reason for this is that if the amount of the pulverized coal is less than 1 wt %, the mercury-based substance 23 in the pyrolyzed gas 14 cannot be adhered and removed sufficiently. If the amount exceeds 10 wt %, an amount that exceeds the amount required for adhering and removing the mercury-based substance 23 in the pyrolyzed gas 14 will be used in a wasteful manner.

Second Embodiment

A second embodiment of a coal pyrolysis device and a modified coal production equipment using the same according to the present invention is described below on the basis of FIGS. 3 and 4. Portions similar to portions in the above-mentioned embodiment are provided with the same reference numerals as used in the explanations for the above-mentioned embodiment and explanations that duplicate explanations of the above-mentioned embodiment will be omitted.

As illustrated in FIG. 3, the one end side (proximal end side) of a pulverized coal feed tube 275 is coupled to the distal end side of the feeder 174. A carrier gas feeding line 276 for supplying the inert gas 12 such as nitrogen gas is coupled to the connecting portion of the distal end side of the feeder 174 and the pulverized coal feed tube 275. The gas sending part of the desulfurization device 164 communicates with outside the system and is coupled to the carrier gas feeding line 276 in the middle thereof via a return line 277 having a return blower 277 a. The other end side (distal end side) of the pulverized coal feed tube 275 is inserted inside the other end side of the inner tube 122 of the coal pyrolysis device 120.

As illustrated in FIG. 4, the other end (distal end) of the pulverized coal feed tube 275 is positioned nearer the other end where a temperature reduction occurs more than the middle in the axial direction of the inside of the inner tube 122 of the coal pyrolysis device 120, that is, at a boundary portion B between a portion covered by the outer tube 123 and heated with the heating gas 17 and the other end side of a portion not covered by the outer tube 123 and not heated with the heating gas 17.

In this embodiment, a pulverized coal supply device 270, which is a pulverized coal supply means, is configured by the pulverized coal conveying device 171, the recovery container 172, the hopper 173, the feeder 174, the pulverized coal feed tube 275, the carrier gas feeding line 276, the return line 276, and the like.

A modified coal production equipment 200 according to this embodiment provided with the pulverized coal supply device 270 as described above is able to manufacture the molded coal 7 from the low grade coal 1 by performing the same principal operations as those performed by the modified coal production equipment 100 in the aforementioned first embodiment.

The waste gas 17 a exhausted from the desulfurization device 164 is fed in addition to the inert gas 12 to the carrier gas feeding line 276 by the return blower 277 a in the return line 277, and when the pulverized coal 4 a (particle diameter: 100 μm or less) inside the hopper 173 is fed by the feeder 174 to the one end side (proximal end side) of the pulverized coal feed tube 275 so that the volume of the pulverized coal 4 a is 1-10 wt % (preferably 3-5 wt %) relative to the amount of the pyrolyzed coal 3 sent from the other end side of the inner tube 122 in the coal pyrolysis device 120, the pulverized coal 4 a is carried by gas flow toward the other end side (distal end side) inside the pulverized coal feed tube 275 by a carrier gas 24 comprising the waste gas 17 a and the inert gas 12, and the pulverized coal 4 a is supplied without being heated by the heating gas 17 to the boundary portion B inside the inner tube 122 of the coal pyrolysis device 120.

The pulverized coal 4 a supplied to the boundary portion B without being heated inside the inner tube 122 of the coal pyrolysis device 120 in this way is moved from the one end side toward the other end side inside the inner tube 122 and is positioned at the boundary portion B with a temperature (approximately 50° C.) much lower than the temperature of the pyrolyzed coal 3 (approximately 350 to 450° C.) subjected to pyrolysis under heat, whereby more of the mercury-based substance 23 in the pyrolyzed gas 14 actively adheres to the pulverized coal 4 a than to the pyrolyzed coal 3.

As a result, an increase in the mercury concentration of the pyrolyzed coal 3 sent from the chute 124 of the coal pyrolysis device 120 is further suppressed than in the above-mentioned embodiment.

Therefore, an increase in the generated mercury concentration in the pyrolyzed coal 3 to be generated can be further suppressed according to this embodiment than in the above-described embodiment.

Third Embodiment

A third embodiment of a coal pyrolysis device and a modified coal production equipment using the same according to the present invention is described below on the basis of FIG. 5. Portions similar to portions in the previous embodiments are provided with the same reference numerals as used in the explanations for the previous embodiments and explanations that duplicate explanations of the previous embodiments will be omitted.

As illustrated in FIG. 5, a pyrolyzed coal extracting line 371 for extracting a portion of the pyrolyzed coal 3 carried by the pyrolyzed coal conveying line 139 is connected to the pyrolyzed coal conveying line 139 in the middle thereof. The pyrolyzed coal extracting line 371 communicates with a pyrolyzed coal conveying device 372 for conveying the pyrolyzed coal 3 extracted by the pyrolyzed coal extracting line 371. The first side (left side in FIG. 5) of the pyrolyzed coal conveying device 372 communicates with the pyrolyzed coal conveying line 139 in the middle thereof via a pyrolyzed coal return line 373.

The second side (right side in FIG. 5) of the pyrolyzed coal conveying device 372 communicates with a hopper 374 for receiving the pyrolyzed coal 3. A lower part of the hopper 374 is coupled to a proximal end side of a feeder 375 for sending in fixed amounts the pyrolyzed coal 3 inside the hopper 374. The distal end side of the feeder 375 communicates with a receiving part of a pulverizing device 376 for pulverizing (particle diameter: 100 μm or less) the pyrolyzed coal 3. A sending part of the pulverizing device 376 communicates with a receiving port of the hopper 173 via a conveyor 376.

In this embodiment, a pulverized coal manufacturing device 370 is configured by the pyrolyzed coal extracting line 371, the pyrolyzed coal conveying device 372, the pyrolyzed coal return line 373, the hopper 374, the feeder 375, the pulverizing device 376, and the like, and a pulverized coal supply means is configured by the pulverized coal supply device 270, the pulverized coal manufacturing device 370, and the like.

A modified coal production equipment 300 according to this embodiment provided with the pulverized coal supply device 170 and the pulverized coal manufacturing device 370, and the like as described above is able to manufacture the molded coal 7 from the low grade coal 1 by performing the same principal operations as those performed by the modified coal production equipment 100 in the aforementioned first embodiment.

Moreover, when the amount of the pulverized coal 2 a supplied to the hopper 173 via the pulverized coal conveying device 171 from the cyclone separator 144 in the deactivation treatment device 140 is insufficient, a portion of the pyrolyzed coal 3 conveyed by the pyrolyzed coal conveying line 139 is extracted from the pyrolyzed coal extracting line 371 and supplied to the hopper 374 via the pyrolyzed coal conveying device 372 and fed in fixed amounts into the pulverizing device 376 by the feeder 375, whereby the pyrolyzed coal 3 is pulverized (particle diameter: 100 μm or less) to form pulverized coal 3 a which is supplied to the hopper 173.

At this time, if the amount of coal 3 or 3 a supplied to the hoppers 173 or 374 is excessive, the pyrolyzed coal conveying device 372 is made to operate in the reverse direction so as to return the pyrolyzed coal 3 extracted from the pyrolyzed coal conveying line 139 to the pyrolyzed coal conveying line 139 via the pyrolyzed coal return line 373.

As a result, even if the amount of the pulverized coal 3 a recovered with the cyclone separator 144 of the deactivation treatment device 140 becomes too small, a sufficient amount of the pulverized coal 3 a and 4 a can be constantly supplied to the inner tube 122 of the coal pyrolysis device 120.

Thus, according to this embodiment, the same effects as the previous embodiments can be realized and moreover the suppression of an increase in the mercury concentration in the pyrolyzed coal 3 can be conducted in a more stable manner than the previous embodiments.

Fourth Embodiment

A fourth embodiment of a coal pyrolysis device and a modified coal production equipment using the same according to the present invention is described below on the basis of FIG. 6. Portions similar to portions in the previous embodiments are provided with the same reference numerals as used in the explanations for the previous embodiments and explanations that duplicate explanations of the previous embodiments will be omitted.

As illustrated in FIG. 6, a lower part of the cyclone separator 117 of the coal drying device 110 communicates with a pulverized coal conveying device 471 for conveying from the cyclone separator 117 the pulverized coal 2 a separated from the inert gas 12. The first side (left side in FIG. 6) of the pulverized coal conveying device 471 communicates with a recovery container 472 for recovering the pulverized coal 2 a. The second side (right side in FIG. 6) of the pulverized coal conveying device 471 communicates with a hopper 473 for receiving the pulverized coal 2 a. A lower part of the hopper 473 is coupled to a proximal end side of a feeder 474 for sending in fixed amounts the pulverized coal 2 a inside the hopper 473. The distal end side of the feeder 474 communicates with the dried coal conveying line 119 of the coal drying device 110.

In this embodiment, a pulverized coal supply device 470 is configured by the pulverized coal conveying device 471, the recovery container 472, the hopper 473, the feeder 474, and the like, and a pulverized coal supply means is configured by the pulverized coal supply devices 270 and 470, pulverized coal manufacturing device 370, and the like.

A modified coal production equipment 400 according to this embodiment that configures a pulverized coal supply means with the pulverized coal supply devices 270 and 470, the pulverized coal manufacturing device 370, and the like as described above is able to manufacture the molded coal 7 from the low grade coal 1 by performing the same principal operations as those performed by the modified coal production equipment 100 in the aforementioned first embodiment.

Moreover, the pulverized coal 2 a (particle diameter: 100 μm or less) separated and recovered with the cyclone separator 117 of the coal drying device 110 is supplied to the hopper 473 via the pulverized coal conveying device 471, supplied in fixed amounts by the feeder 474 to the dried coal conveying line 119 of the coal drying device 110, and supplied along with the dried coal 2 from the hopper 121 of the coal pyrolysis device 120 into the inner tube 122, and the pulverized coal 3 a and 4 a are fed in fixed amounts with the feeder 174 so that the total volume of the pulverized coal 3 a and 4 a and the pulverized coal 2 a supplied into the inner tube 122 is 1-10 wt % (preferably 3-5 wt %) relative to the amount of the pyrolyzed coal 3 sent from the other end side of the inner tube 122 in the coal pyrolysis device 120, and supplied into the inner tube 122 of the coal pyrolysis device 120 via the pulverized coal feed tube 275 with the carrier gas 24.

If the amount of the pulverized coal 2 a supplied from the cyclone separator 117 into the hopper 473 is too much, the pulverized coal conveying device 471 is made to operate temporarily in the reverse direction so that the excess pulverized coal 2 a is recovered in the recovery container 472.

That is, an increase in mercury concentration in the pyrolyzed coal 3 is suppressed in this embodiment by using the pulverized coal 2 a separated and recovered from the inert gas 12 generated accompanying the drying of the low grade coal 1 in the coal drying device 110.

Thus, according to this embodiment, the same effects as the previous embodiments can be realized and moreover the generated amount of the molded coal 7 can be increased in comparison to the third embodiment described above because a portion of the pyrolyzed coal 3 conveyed by the pyrolyzed coal conveying line 139 is extracted and pulverized with the pulverizing device 376 so that the usage amount of the pulverized coal 3 a to be replenished is reduced.

Fifth Embodiment

A fifth embodiment of a coal pyrolysis device and a modified coal production equipment using the same according to the present invention is described below on the basis of FIG. 7. Portions similar to portions in the previous embodiments are provided with the same reference numerals as used in the explanations for the previous embodiments and explanations that duplicate explanations of the previous embodiments will be omitted.

As illustrated in FIG. 7, an exhaust nozzle 529 for sending out the pyrolyzed gas 14 from the other end side of the inner tube 122 is provided in the chute 124 of the coal pyrolysis device 120. The exhaust nozzle 529 is disposed so that the proximal end side (one end side) thereof is coupled to the proximal end side (one end side) of the exhaust line 126, and a receiving port 529 a on the distal end (other end) is positioned between an uppermost position DH of an opening part (port for coupling with the chute 124) 122 a on the other end side of the inner tube 122 and a surface position CF of the layer of the pyrolyzed coal 3 present in the lowest position DL portion of an opening part (port for coupling with the chute 124) 122 a on the other end side of the inner tube 122.

A modified coal production equipment 500 according to this embodiment provided with the coal pyrolysis device 120 having the exhaust nozzle 529 as described above is able to manufacture the molded coal 7 from the low grade coal 1 by performing the same principal operations as those performed by the modified coal production equipment 100 in the aforementioned first embodiment.

At this time, the amount of the pulverized coal 2 a to 4 a following the pyrolyzed coal 3 that falls inside the chute 124 can be reduced because the receiving port 529 a of the exhaust nozzle 529 is positioned between the uppermost position DH and the surface position CF, the pulverized coal 2 a to 4 a floating inside the inner tube 122 is brought nearer an inflow port of the exhaust line 126 in which the pyrolyzed gas 14 circulates at a speed faster than the circulation speed inside the inner tube 122.

Thus, according to this embodiment, the same effects as the previous embodiments can be realized and moreover the suppression of an increase in mercury concentration in the pyrolyzed coal 3 can be conducted more reliably than the previous embodiments.

Sixth Embodiment

A sixth embodiment of a coal pyrolysis device and a modified coal production equipment using the same according to the present invention is described below on the basis of FIG. 8. Portions similar to portions in the previous embodiments are provided with the same reference numerals as used in the explanations for the previous embodiments and explanations that duplicate explanations of the previous embodiments will be omitted.

As illustrated in FIG. 8, a gas sending part of the NOx removal device 162 communicates with a gas receiving part of a desulfurization device 663 for blowing a calcium hydroxide slurry 25 into the waste gas 17 a. A sending part of the desulfurization device 663 communicates with a receiving part of a bag filter 664 for separating and removing dust and the like in the waste gas 17 a. A gas sending part of the bag filter 664 communicates with outside the system. An activated carbon injection device 665 for injecting activated carbon 26 into the waste gas 17 a is connected between the desulfurization device 663 and the bag filter 664.

That is, while the explanation was provided that the waste gas treatment device 160 (wet desulfurization method) in the modified coal production equipment 100, 200, 300, 400, and 500 according to the aforementioned embodiments is used to replace nitrogen oxides such as nitric monoxide with nitrogen gas (see formula (1)) by atomizing the ammonium chloride aqueous solution 21 into the waste gas 17 a with the NOx removal device 162, and after mercury is replaced by mercury chloride (see formula (2)) and after the dust and the like is separated and removed by the electric dust collection device 163, the calcium carbonate slurry 22 is blown into the waste gas 17 a with the desulfurization device 164 so that the mercury chloride is dissolved in water and recovered (see formula (3)), and sulfur oxides such as sulfur dioxide are recovered by being replaced by calcium sulfate and the like (see formula (4) and (5)). However, in this embodiment, a waste gas treatment device 660 (dry desulfurization method) is used to replace nitrogen oxides such as nitric monoxide with nitrogen gas (see formula (1)) by atomizing the ammonium chloride aqueous solution 21 into the waste gas 17 a with the NOx removal device 162, and after mercury is replaced by mercury chloride (see formula (2)), while the sulfur oxides such as sulfur dioxide are replaced by calcium sulfate and the like (see formulas (6) and (7) below) by blowing the calcium hydroxide slurry 25 into the waste gas 17 a with the desulfurization device 663, the activated carbon 26 is injected into the waste gas 17 a with the activated carbon injection device 665 so that the mercury chloride adheres to the activated carbon 26 whereby the calcium sulfate and the activated carbon 26 are separated and recovered with the bag filter 664.

SO₂+Ca(OH)₂→CaSO₃.½H₂O+½H₂O  (6)

CaSO₃.½H₂O+½O₂+3/2H₂O→CaSO₄. 2H₂O  (7)

Thus, according to this embodiment, the same effects as the previous embodiments are realized.

Other Embodiments

While the modified coal production equipment 300 in which the pulverized coal supply means is configured by the pulverized coal supply device 270, the pulverized coal manufacturing device 370, and the like is described in the above-mentioned third embodiment, as another embodiment, for example, a pulverized coal supply means may be configured by omitting the pulverized coal supply device 270 to supply the pulverized coal 3 a obtained by the pulverized coal manufacturing device 370 to the inner tube 122 of the coal pyrolysis device 120 via the pulverized coal feed tube 275 or the hopper 111.

Moreover, while the modified coal production equipment 400 that configures the pulverized coal supply means with the pulverized coal supply devices 270 and 470, the pulverized coal manufacturing device 370, and the like is described in the aforementioned fourth embodiment, as another embodiment, for example, the pulverized coal supply means may be configured by omitting the pulverized coal manufacturing device 370 to supply the pulverized coal 2 a and 4 a obtained with the pulverized coal supply devices 270 and 470 to the inner tube 122 of the coal pyrolysis device 120 via the pulverized coal feed tube 275 or the hopper 111, or the pulverized coal supply means may be configured by omitting the pulverized coal supply device 270 to supply the pulverized coal 2 a and 4 a obtained with the pulverized coal supply device 470 and the pulverized coal manufacturing device 370 to the inner tube 122 of the coal pyrolysis device 120 via the pulverized coal feed tube 275 or the hopper 111, or furthermore, the pulverized coal supply means may be configured by omitting the both pulverized coal supply device 270 and the pulverized coal manufacturing device 370 to supply the pulverized coal 2 a obtained with the pulverized coal supply device 470 to the inner tube 122 of the coal pyrolysis device 120 via the pulverized coal feed tube 275 or the hopper 111.

Furthermore, while in the aforementioned sixth embodiment, sulfur oxides such as sulfur dioxide is replaced by calcium sulfate and the like by blowing the calcium hydroxide slurry 25 into the waste gas 17 a with the desulfurization device 663 by connecting the activated carbon injection device 665 between the desulfurization device 663 and the bag filter 664, and then after the activated carbon 26 are injected into the waste gas 17 a with the activated carbon injection device 665 to make the mercury chloride adheres to the activated carbon 26, the calcium sulfate and the activated carbon 26 are separated and recovered with the bag filter 664, as another embodiment for example, the activated carbon 26 is injected into the waste gas 17 a with the activated carbon injection device 665 to make the mercury chloride adhere to the activated carbon 26 by connecting the activated carbon injection device 665 between the NOx removal device 162 and the desulfurization device 663, and then after the sulfur oxides such as sulfur dioxide are replaced by calcium sulfate and the like by blowing the calcium hydroxide slurry 25 into the waste gas 17 a with the desulfurization device 663, the calcium sulfate and the activated carbon 26 are separated and recovered with the bag filter 664, or for example, after the sulfur oxides such as sulfur dioxide are replaced by calcium sulfate and the like by blowing the calcium hydroxide slurry 25 into the waste gas 17 a with the desulfurization device 663 by connecting the activated carbon injection device 665 to the desulfurization device 663, and the activated carbon 26 is injected into the waste gas 17 a with the activated carbon injection device 665 to make the mercury chloride adhere to the activated carbon 26, the calcium sulfate and the activated carbon 26 can be separated and recovered with the bag filter 664.

INDUSTRIAL APPLICABILITY

The coal pyrolysis device and the modified coal production equipment that uses the coal pyrolysis device according to the present invention are able to suppress an increase in generated mercury concentration in pyrolyzed coal and thus can be used in a very advantageous manner in industrial applications.

REFERENCE SIGNS LIST

-   1 Low grade coal (low rank coal) -   2 Dried coal -   2 a Pulverized coal -   3 Pyrolyzed coal -   3 a Pulverized coal -   4 Modified coal -   4 a Pulverized coal -   5 Binder -   6 Water -   7 Molded coal -   11 Steam -   12 Inert gas -   13 Water -   14 Pyrolyzed gas -   15 Air -   16 Combustion improver -   17 Heating gas -   17 a Waste gas -   18 Cooling water -   19 Waste air -   20 Water vapor -   21 Ammonium chloride aqueous solution -   22 Calcium carbonate slurry -   23 Mercury-based substance -   24 Carrier gas -   25 Calcium hydroxide slurry -   26 Activated carbon -   100 Modified coal production equipment -   110 Coal drying device -   111 Hopper -   112 Inner tube (main body trunk) -   113 Outer tube (jacket) -   114 Chute -   115 Inert gas feeding line -   116 Exhaust line -   117 Cyclone separator -   118 Recirculating line -   118 a Condenser -   119 Dried coal conveying line -   120 Coal pyrolysis device -   121 Hopper -   122 Inner tube (main body trunk) -   122 a Opening -   123 Outer tube (jacket) -   124 Chute -   125 Heating gas feeding line -   126 Exhaust line -   127 Combustion furnace -   128 Extracting line -   130 Cooling device -   131 Hopper -   132 Inner tube -   133 Outer tube -   134 Chute -   139 Pyrolyzed coal conveying line -   140 Deactivation treatment device -   141 Tower body -   142 Air feeding line -   142 a Air blower -   143 Waste air line -   144 Cyclone separator -   150 Molded coal manufacturing device -   151 Kneading device -   152 Molding device -   160 Waste gas treatment device -   161 Waste gas line -   161 a Sending blower -   161 b Condenser -   162 NOx removal device -   163 Electric dust collection device -   164 Desulfurization device -   170 Pulverized coal supply device -   171 Pulverized coal conveying device -   172 Recovery container -   173 Hopper -   174 Feeder -   175 Conveyor -   200 Modified coal production equipment -   270 Pulverized coal supply device -   275 Pulverized coal feeding tube -   276 Carrier gas feeding line -   277 Return line -   277 a Return blower -   300 Modified coal production equipment -   370 Pulverized coal manufacturing device -   371 Pyrolyzed coal extracting line -   372 Pyrolyzed coal conveying device -   373 Pyrolyzed coal return line -   374 Hopper -   375 Feeder -   376 Pulverizing device -   400 Modified coal -   470 Pulverized coal supply device -   471 Recovery container -   472 Recovery container -   473 Hopper -   474 Feeder -   500 Modified coal production equipment -   529 Exhaust nozzle -   529 a Receiving port -   660 Waste gas treatment device -   663 Desulfurization device -   664 Bag filter -   665 Activated carbon injection device 

1. A rotary kiln-type coal pyrolysis device that rotatably supports an inner tube inside an outer tube and that pyrolyzes under heat while moving and agitating coal from one end side of the inner tube to another end side thereof by rotating the inner tube upon heating gas being supplied to an interior of the outer tube and upon the coal being supplied from the one end side of the inner tube to an interior thereof, so as to send out pyrolyzed coal and pyrolyzed gas from the other end side of the inner tube, the coal pyrolysis device, comprising: a pulverized coal supply means that supplies pulverized coal having a particle diameter of less than or equal to 100 μm to the interior of the inner tube, such that a volume of the pulverized coal is 1-10 wt % relative to an amount of the pyrolyzed coal sent from the other end side of the inner tube.
 2. The coal pyrolysis device according to claim 1, wherein the pulverized coal supply means supplies the pulverized coal nearer the other end where a temperature reduction occurs than a middle in an axial direction inside the inner tube.
 3. The coal pyrolysis device according to claim 1, wherein an exhaust nozzle is provided so that a distal end thereof is positioned between an uppermost position of an opening on the other end side of the inner tube and a surface position of a layer of the pyrolyzed coal present in a lowest position of the opening on the other end side of the inner tube so as to send out the pyrolyzed gas from the other end side of the inner tube.
 4. A modified coal production equipment, comprising: a coal drying means for drying coal; and the coal pyrolysis device described in claim 1 for pyrolyzing dried coal dried with the coal drying means.
 5. The modified coal production equipment according to claim 4, further comprising a pyrolyzed coal cooling means for cooling the pyrolyzed coal pyrolyzed by the coal pyrolysis device.
 6. The modified coal production equipment according to claim 5, further comprising a deactivation treatment means for deactivating the pyrolyzed coal cooled by the pyrolyzed coal cooling means using an oxygen-containing gas.
 7. The modified coal production equipment according to claim 4, wherein the pulverized coal supply means supplies pulverized coal generated and recovered accompanying the drying of the coal by the coal drying means.
 8. The modified coal production equipment according to claim 5, wherein the pulverized coal supply means supplies pulverized coal that is a portion of the pyrolyzed coal cooled by the pyrolyzed coal cooling means that is extracted and pulverized.
 9. The modified coal production equipment according to claim 6, wherein the pulverized coal supply means supplies pulverized coal recovered from the oxygen-containing gas used in the deactivation treatment of the pyrolyzed coal by the deactivation treatment means. 